Many molecular and cell biology techniques involve identification and isolation of target cells from a population of cells. Some of these methods also require maintaining viability of the target cells after isolation. Thus, there is a need for screening apparatuses and methods that enable easy monitoring of target cells amongst the population of cells followed by selective extraction of the target cells for further analysis.
One such technique is mutagenesis in a population of cells. Mutagenesis is a powerful technique to produce target cells, for example, micro-organisms or cultured cells, capable of producing proteins, enzymes, or metabolites of interest. Coupled with screening or selection systems, mutagenesis has been successfully employed in various fields. Conventionally, screening and selection are conducted by culturing mutagenized populations, for example, mutagenized micro-organisms or cultured cells, at low dilution on culture plates and manually picking cells showing the desired trait. Although this process is useful and widely used, it is time-consuming and labor-intensive. Also, mutagenesis is costly and challenging because a large numbers of mutants (e.g. 1,000 to 1,000,000 mutants) may need to be screened to find one genetic variant showing the desired properties. Thus, there is also a need for a mutagenized cell screening platform that enables easy monitoring of mutagenized cells followed by selective extraction of a particular genetic variant of interest (“a hit”) for further off-chip analysis and sampling.